PARENT SESSION
Oral Session #32: Testing Ecological Theory in Restoration Practice.
Presiding: C. Brown
Tuesday, August 6. 8:00 AM to 11:30 AM. Grand Ballroom West, Radisson.
Using successional management to restore invasive plant dominated wildlands.
ANDERSON, JENNIFER*,1, JACOBS, JAMES1, SHELEY, ROGER1, 1 MONTANA STATE UNIVERSITY, BOZEMAN, MT
ABSTRACT- Invasive plant management must progress from simply treating symptoms to modifying processes that cause plant community dynamics. We tested the hypothesis that increasingly addressing the three general causes of succession; disturbance, colonization, and species performance, would enhance the establishment of native species during restoration. Our specific objective was to determine if we could improve establishment of Festuca idahoensis or Agropyron spicatum in a Centaurea maculosa infested rangeland by addressing the three general causes of succession. Colonization included seeding the native grasses at 1000 seeds m-2 and 2000 seeds m-2. Disturbance was achieved using 3 seeding methods [broadcast, no-till drill, and strip-till]. A fungicide (with and without) to influence potential pathogens and picloram (with and without) were used to influence species performance. Treatments were arranged in an incomplete (excluding 2000 seeds m-2 plus fungicide) factorial in a split-plot design with 4 replications the fall of 1997. Grass and spotted knapweed densities were measured in 1998 and 1999. After two years, both grass species had higher densities where they were seeded in combination with picloram. Agropyron spicatum density was higher where it was seeded at the higher density using a no-till drill while the density of Festuca idahoensis was higher where it was broadcast at the higher density or strip-till seeded at both 1000 and 2000 seeds m-2. The fungicide appeared to have little effect on successful establishment. Our study suggests restoration of invasive plant infested wildlands will be most successful where multiple causes of succession are addressed.
KEY WORDS: successional management, invasive plants, native bunchgrasses, restorating native grasses